A University of Colorado economics professor has co-authored a study, just released by the Institute for the Study of Labor in Bonn, Germany that concludes that suicide rates among young males declines markedly after states legalize medical marijuana. Professors at Montana State University and San Diego State University were also involved in the study. The study is titled “High on Life: Medical Marijuana Laws and Suicide.”

CU Denver professor Daniel Rees and his coauthors don’t say conclusively why suicide rates fall. They offer evidence that marijuana acts as an antidepressant when used moderately, but also note that using marijuana in larger amounts can actually lead to depression.

Using state-level data for the period 1990 through 2007, we estimate the effect of legalizing medical marijuana on suicide rates. Our results suggest that the passage of a medical marijuana law is associated with an almost 5 percent reduction in the total suicide rate, an 11 percent reduction in the suicide rate of 20- through 29-year-old males, and a 9 percent reduction in the suicide rate of 30- through 39-year-old males.

We conclude that the legalization of medical marijuana leads to an improvement in the psychological wellbeing of young adult males, an improvement that is reflected in fewer suicides.

In an often-cited article, Hamermesh and Soss (1974) argued that negative shocks to happiness may reduce expected lifetime utility to the point where an individual will decide to take his or her own life. The negative relationship between legalization and suicides among young adult males is consistent with the argument that marijuana can be used to cope with such shocks. However, estimates provided by Anderson et al. (2011) provide an alternative explanation. These authors found that the passage of MMLs (medical marijuana laws) led to sharp decreases in alcohol-related traffic fatalities, self-reported alcohol use, and per capita beer sales. The strong association between alcohol consumption and suicide related outcomes found by previous researchers (Markowitz et al. 2003; Carpenter 2004; Sullivan et al. 2004; Rodriguez Andres 2005; Carpenter and Dobkin 2009) raises the possibility that medical marijuana laws reduce the risk of suicide by decreasing alcohol consumption.

Speaking recently at the University of Denver, Amanda Reiman, Ph.D, the director of research at the Berkeley Patients Group and a lecturer at the University of California, Berkeley, said that marijuana has medical value even for people not suffering from one of the ailments that medical marijuana laws typically allow people to use marijuana for.

“We deontologically believe that drug use is inherently wrong, which is why it is hard for us to believe there are responsible users. Do you really have to be sick to get benefit from cannabis?” she asked rhetorically.

She said that when you ask people why they smoke marijuana, the most common answer is that it helps them relax. “The word medical is redundant when talking about cannabis. Relaxation itself is medicinal.”

Reiman’s words were echoed on the DU panel by University of California law professor Marsha Cohen, who said that when asked why they smoke marijuana, people answer “‘It makes me feel better.’ That makes it medicinal use,” she said.

Mason Tvert, executive director of SAFER (Safer Alternative for Recreational Enjoyment) and one of the organizers of a ballot initiative to regulate marijuana like alcohol, which will probably be on the Colorado ballot in November, said he was not surprised by the study’s conclusions.

“We know marijuana has medicinal value, and we know that people living with pain sometimes kill themselves,” Tvert said. He added that the connection with alcohol use was intriguing. “Every credible study ever done proves that marijuana is safer than alcohol,” he said.